mini stock

[james linden]

i have fitted a weber carb to a 1275 mini engine she starts fine and tics over lovely but when i try to throttle it it dies. But if i cover half of the air intake it revs like billyo i would assume the jetting will need attention but which way do i go can anyone help!

 

[pgarner]

welcome mate. sorry i can t help but i hope someone can

 

[obi_waynne]

Which carb have you fitted is it a twin?

I guess the question to ask is - "is it running lean or rich". Carbs are notoriously tricky to setup. I would guess it is running lean as halving the airflow lets it run fine, so increase the jet size. You also need to ask yourself if the fuel pump delivery is up to the job?

It would be easier to setup if you could get an o2 reading from the exhaust whilst playing with the jets.

 

[james linden]

it is a single dcoe 40 fuel pressure seems fine which jets do i need to make larger the pump jets or the main jets? ( i really dont know alot about carburation at all) sorry_

 

[obi_waynne]

Its been a long time since I played with a Carb but you want the main jet to be larger to make the mix richer. I'm sure some of our older members will be happy to bang on about needles and carb tweaks....

 

[claymore]

my initial thought is to much fuel actually

 

[stamford]

Was it bought second hand or brand new? If it was brand new, did they ask what car it was for? Jetting will only be for a basic set-up to get it running. You really need to rolling road it in order to get it jetted correctly. What else has been done to the engine to warrant a Weber carb?